CVE-2018-15121

An issue was discovered in Auth0 auth0-aspnet and auth0-aspnet-owin. Affected packages do not use or validate the state parameter of the OAuth 2.0 and OpenID Connect protocols. This leaves applications vulnerable to CSRF attacks during authentication and authorization operations.

Published: 2018-08-28 Last update: 2026-06-16 Assigner: [email protected] Source: [email protected]
NVD Status：Modified，CVE State: published
View at NVD, CVE.org, EUVD

CVE-2018-15121 is rated Moderate Risk (48.9/100): CVSS High severity, with low exploitation likelihood (EPSS 0.49%). Review affected assets and schedule remediation.

Risk is dynamic; we continuously reassess and refresh what is shown on this page as upstream context changes.

Exploit prediction scoring system (EPSS) score for CVE-2018-15121

EPSS lead: Daily EPSS estimates relative likelihood of exploitation; percentile ranks this CVE among scored vulnerabilities (higher = more severe relative rank).

# Date Old EPSS score New EPSS score Delta (New - Old)
1 2026-06-15 0.07% 0.49% +0.41%
2 2023-03-07 0.89% 0.07% -0.81%
3 2022-02-04 — 0.89% —

Full EPSS history (4 records total)

Common vulnerability scoring system (CVSS) metrics for CVE-2018-15121

CVSS metrics for this CVE.

Base score Version Severity Vector Exploitability Impact Score source
8.8 3.0 HIGH
CVSS:3.0/AV:N/AC:L/PR:N/UI:R/S:U/C:H/I:H/A:H Click to expand
Attack vector (AV:N)
Could be attacked over the internet or any normal routed network—not just someone sitting at the machine.
Attack complexity (AC:L)
Once they can reach the bug, pulling it off is straightforward—no weird race conditions or rare setup.
Privileges required (PR:N)
No account or special rights needed—anonymous or random user is enough.
User interaction (UI:R)
A real person has to do something—click, install, enable—otherwise it doesn’t land.
Scope (S:U)
Damage stays in the same “trust bubble” as the broken component—no big spill into unrelated systems.
Confidentiality (C:H)
Serious risk that confidential data gets exposed in a big way.
Integrity (I:H)
They could widely tamper with or forge data—trust in the data is badly hurt.
Availability (A:H)
Could take the service down hard or make it unusable for people who depend on it.
 2.8 5.9 [email protected]
6.8 2.0 MEDIUM
AV:N/AC:M/Au:N/C:P/I:P/A:P Click to expand
Access vector (AV:N)
Can be exploited remotely over network reachability.
Access complexity (AC:M)
Exploitation needs some favorable conditions, but not exceptional ones.
Authentication (AU:N)
No authentication is required.
Confidentiality impact (C:P)
Partial confidentiality impact.
Integrity impact (I:P)
Partial integrity impact.
Availability impact (A:P)
Partial availability impact.
 8.6 6.4 [email protected]

Weakness enumeration for CVE-2018-15121

GitHub Security Advisory for CVE-2018-15121

GHSA-mmhr-3jr7-qj2p · Severity: high · Ecosystem: nuget — Auth0-ASPNET and Auth0-ASPNET-Owin vulnerable to Cross-Site Request Forgery

Affected software / configurations for CVE-2018-15121

Vendor Product Version Raw CPE
auth0 aspnet — cpe:2.3:a:auth0:aspnet:-:*:*:*:*:*:*:*
auth0 aspnet-owin — cpe:2.3:a:auth0:aspnet-owin:-:*:*:*:*:*:*:*

References for CVE-2018-15121

cvelogic Threat Intelligence